Evaluating human caused ocean damage

Dr. Whitford covered a wide range of adverse impacts humans are having on the oceans; this article presents a few of them. He began his presentation with the issue of the global waste dumping, particularly plastics which deteriorate into near nanoparticle sizes and occupy the top three to four feet of ocean waters. Filter feeders take in the particles along with the floating diatoms that provide their nourishment. Plastics damage development and serve as endocrine disrupters as they are passed up to larger creatures in the food chain.

Some 270 billion water bottles per year are produced but not recycled. While no solutions are in sight, swirls of plastics are visible from space in the ocean just beneath Japan.

Nearly all the world’s major river systems have dead zones where they empty into the oceans. The dead zone in the Gulf of Mexico occurs where the Mississippi River empties into it. It is about 75 miles offshore and is devoid of many life forms as such areas are depleted of oxygen which was consumed in the breakdown of organic debris. The river brings all the chemicals that wash into it from their use in the watershed. Artificially produced estrogen gets into our drinking water adversely impacting human reproduction and contributes to accumulation of trans fats as plaque in our hearts and fat in our bellies.

Agricultural chemicals enter our waters, drain into our rivers, and work their way into our ground water. Pollution from large animal operations could be dramatically reduced with tertiary treatment of the wastes but such a solution faces stiff opposition. If tertiary treatment were applied to sewage plants treating human wastes, estrogen would remain.

As a professor Dr. Whitford held an annual student fishing contest one mile below a sewage treatment plant on the Cuyahoga River in Ohio to demonstrate the adverse impacts of chemicals on fish. The student who caught the fish with the most tumors was declared the winner.

Ocean fish are being depleted as exemplified by the collapse of the cod fishery in the North Atlantic. The Orange roughly has diminished by 90 percent since its commercial harvest began in 1978. Some stores refuse to sell it. Even the prized tuna is rapidly declining in number and size under the pressure of five million hooks on 100,000 miles of line every day in the Pacific Ocean.

Acceleration of global trade has increased invasive species from bilge water picked up in distant ports to stabilize ships when cargo is unloaded. It is discharged to local waters as more cargo is loaded. One hundred fifteen introduced species live in Lake Michigan. Some, such as zebra mussels, have an adverse impact on lake ecology.

Upper layers of the ocean absorb atmospheric carbon dioxide turning the waters more acidic. Acidified waters inhibit shell growth in marine animals and can disrupt reproduction in some fish.

Whitford has documented the damage done to coral reefs. At the Caribbean research site the number of cruise ships increased from two per week in 1998 to about 14 by 2016. To accommodate the ships, ports are developed using coral sand from the ocean floor stirring up silt which drifts onto the coral. A half inch of silt deprives the coral of oxygen, killing it.

Cruise passengers slather themselves with sunscreen before they enter the water to swim and dive. Four sunscreen chemicals in the water are toxic to coral at levels of 2 ppm. Fortunately, certified reef safe sunscreens can be used to eliminate the problem.

We highlighted a small portion of the disheartening information about ongoing human caused environmental deterioration in the world’s oceans. While energy efficiency and renewable energy sources address the climate change issue other corrective actions are essential to save the planet.